Imaging of evoked dense-core-vesicle exocytosis in hippocampal neurons reveals long latencies and kiss-and-run fusion events.

ABSTRACT: Evoked neuropeptide secretion in the central nervous system occurs slowly, but the basis for slow release is not fully understood. Whereas exocytosis of single synaptic vesicles in neurons and of dense-core vesicles (DCVs) in endocrine cells have been directly visualized, single DCV exocytic events in neurons of the central nervous system have not been previously studied. We imaged DCV exocytosis in primary cultured hippocampal neurons using fluorescent propeptide cargo and total internal reflectance fluorescence microscopy. The majority of Ca(2+)-triggered exocytic events occurred from immobile plasma-membrane-proximal DCVs in the cell soma, whereas there were few events in the neurites. Strikingly, DCVs in the cell soma exhibited 50-fold greater release probabilities than those in neurit

SUBMITTER: Xia X 

PROVIDER: S-EPMC2714402 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature